I'm impressed! Really! This is a very nice portrait. Excellent use of lighting, dof, and she looks very natural, not like posing.
My sincere compliments.
(sidenote: I once had a Bronica ETRS, I sold it, but if I had taken even one picture this good, I'm sure I would still have it!)
She looks pensive and thoughtful, and the soft light has allowed her to be wonderfully wide-eyed and 'open'. If I were her parent I'd love this..."my daughter" in a way I might not usually get to see.
I'm partial to portraits that not only include the hands, but include them in a slightly awkward or unusual position -- not a "straight out of ever portrait text you've ever seen" position.
Y'know, it sure would be nice if in your Copious Spare Time you wrote an article for APUG all about the part of portraiture that has nothing to do with equipment and materials.
I imagine you approached this girl cold, having not met her before, and connected with her on a subject that elicited a particular emotion, making the camera disappear.
People talk at length about this film over that film, and what lens gives more lines per millimeter, and how to best develop for edge effect, but none of that stuff will advance you one micron toward good pictures if you don't have a mastery of the non-gear/non-equipment part of photography.
I don't see that being discussed much. I wish it would be.